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Ammoniomagnesiovoltaite

A valid IMA mineral species
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07250900017586474167954.jpg
Ammoniomagnesiovoltaite

Pécs-Vasas, Pécs District, Baranya County, Hungary
03906510017875784754314.jpg
Ammoniomagnesiovoltaite, etc.

Pécs-Vasas, Pécs District, Baranya County, Hungary
02346380017367247784894.jpg
Ammoniomagnesiovoltaite

Pécs-Vasas, Pécs District, Baranya County, Hungary
01319950017272471856862.jpg
Ammoniomagnesiovoltaite

Pécs-Vasas, Pécs District, Baranya County, Hungary
03782510017271982357882.jpg
Ammoniomagnesiovoltaite, etc.

Pécs-Vasas, Pécs District, Baranya County, Hungary
07827180017365066163794.jpg
Ammoniomagnesiovoltaite

Pécs-Vasas, Pécs District, Baranya County, Hungary
01319950017272471856862.jpg
Ammoniomagnesiovoltaite

Pécs-Vasas, Pécs District, Baranya County, Hungary
03782510017271982357882.jpg
Ammoniomagnesiovoltaite, etc.

Pécs-Vasas, Pécs District, Baranya County, Hungary
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About AmmoniomagnesiovoltaiteHide

06483340017271927638487.jpg
Alessandro Giuseppe Antonio Anastasio Volta
Formula:
(NH4)2Mg2+5Fe3+3Al(SO4)12 · 18H2O
Colour:
Pale yellow to yellowish brown
Lustre:
Vitreous
Hardness:
2 - 3
Specific Gravity:
2.55
Crystal System:
Isometric
Member of:
Voltaite Group
Name:
The root species name, voltaite, is named after Count Alessandro Giuseppe Antonio Anastasio Volta (18 February 1745, Como, Italy - 5 March 1827, Como, Italy), physicist and pioneer in electricity who invented the electric battery. The prefix "ammoniomagnesio" alludes to the components of ammonium and magnesium substituting for potassium and ferrous iron in voltaite.
Voltaite Group.
Ammonium-magnesium-analogue of voltaite.


Unique IdentifiersHide

Mindat ID:
39666
Long-form identifier:
mindat:1:1:39666:6

IMA Classification of AmmoniomagnesiovoltaiteHide

Classification of AmmoniomagnesiovoltaiteHide

Strunz-mindat (2026):
7.CC.25

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
C : Sulfates (selenates, etc.) without additional anions, with H2O
C : With medium-sized and large cations
Dana 8th ed.:
29.9.1.4

29 : HYDRATED ACID AND NORMAL SULFATES
9 : Miscellaneous

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
AmvltIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of AmmoniomagnesiovoltaiteHide

Lustre:
Vitreous
Transparency:
Translucent
Colour:
Pale yellow to yellowish brown
Streak:
White
Hardness:
2 - 3 on Mohs scale
Tenacity:
Very brittle
Cleavage:
None Observed
Fracture:
Irregular/Uneven
Density:
2.55(1) g/cm3 (Measured)    2.351 g/cm3 (Calculated)

Optical Data of AmmoniomagnesiovoltaiteHide

Type:
Isotropic
RI values:
n = 1.60(1)
Surface Relief:
Moderate (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).

This shows the grain boundary and Becke line effect under plane-polarised light, based on the contrast between this mineral's average refractive index and the mounting medium. It does not take into account mineral colouration.
In focus

Chemistry of AmmoniomagnesiovoltaiteHide

Mindat Formula:
(NH4)2Mg2+5Fe3+3Al(SO4)12 · 18H2O
Element Weights:
Element% weight
O57.730 %
S21.036 %
Fe9.159 %
Mg6.644 %
H2.425 %
N1.532 %
Al1.475 %

Calculated from ideal end-member formula.
O
S
Fe
Mg
H
N
Al
Elements listed:
Al, Fe, H, Mg, N, O, S - search for minerals with similar chemistry

Crystallography of AmmoniomagnesiovoltaiteHide

Crystal System:
Isometric
Class (H-M):
m3m(4/m32/m) - Hexoctahedral
Space Group:
Fd3c
Cell Parameters:
a = 27.260(2) Å
Unit Cell V:
20257 ų
Z:
16
Morphology:
Type material: Crystal forms identified by SEM are {111}, {100}, and minor {110}.
Twinning:
Not observed.
Comment:
Cell parameters from Szakáll et al. (2012).

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
6.85 Å(24)
5.59 Å(100)
3.562 Å(66)
3.420 Å(72)
3.059 Å(22)
2.197 Å(22)
1.784 Å(25)
1.558 Å(25)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 7: Great Oxidation Event<2.4
47b : [Sulfates and sulfites]
Stage 10b: Anthropogenic minerals<10 Ka
55 : Anthropogenic mine minerals

Type Occurrence of AmmoniomagnesiovoltaiteHide

Type Locality:
ⓘ Pécs-Vasas, Pécs District, Baranya County, Hungary
General Appearance of Type Material:
Crusts consisting of cubo-octahedral and octahedral crystals up to 0.05 mm in size.
Place of Conservation of Type Material:
Herman Ottó Museum, Miskolc, Hungary (part of the holotype, catalogue number: 2008.233).
Department of Mineralogy and Petrology, Hungarian Natural History Museum, Budapest, Hungary, (part of the holotype, catalogue number: Gyn.1590).
Geological Setting of Type Material:
Burning coal dump. Formed by the interaction of organic matter with oxidizing iron sulfides (pyrite and marcasite).
Associated Minerals at Type Locality:
HexahydriteKieseritePickeringiteSabieiteTschermigite
Reference:
Szakáll, S., Sajo, I., Fehér, B., Bigi, S. (2012) Ammoniomagnesiovoltaite, a new voltaite-related mineral species from Pécs-Vasas, Hungary. The Canadian Mineralogist, 50 (1). 65-72 doi:10.3749/canmin.50.1.65

Synonyms of AmmoniomagnesiovoltaiteHide

Other Language Names for AmmoniomagnesiovoltaiteHide

Relationship of Ammoniomagnesiovoltaite to other SpeciesHide

Member of:
Voltaite Group
Other Members of Voltaite Group:
Ammoniovoltaite(NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18Iso. m3m(4/m32/m) : Fd3c
MagnesiovoltaiteK2Mg5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe3+2Al(SO4)12 · 18H2OTet. 4/mmm(4/m2/m2/m) : I41/acd
VoltaiteK2Fe2+5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
ZincovoltaiteK2Zn5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c

Common AssociatesHide

Associations Based on Photo Data:
3 photos of Ammoniomagnesiovoltaite associated with Tschermigite(NH4)Al(SO4)2 · 12H2O
1 photo of Ammoniomagnesiovoltaite associated with Sabieite(NH4)Fe3+(SO4)2
1 photo of Ammoniomagnesiovoltaite associated with Ammoniojarosite(NH4)Fe3+3(SO4)2(OH)6
1 photo of Ammoniomagnesiovoltaite associated with HalotrichiteFe2+Al2(SO4)4 · 22H2O
1 photo of Ammoniomagnesiovoltaite associated with Clairite(NH4)2Fe3(SO4)4(OH)3 · 3H2O
1 photo of Ammoniomagnesiovoltaite associated with BassaniteCa(SO4) · 0.5H2O

Related Minerals - Strunz-mindat GroupingHide

7.CC.CobaltoblöditeNa2Co(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.AndychristyitePbCu2+Te6+O5(H2O)Tric. 1 : P1
7.CC.Ammoniovoltaite(NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18Iso. m3m(4/m32/m) : Fd3c
7.CC.05KrausiteKFe(SO4)2 · H2OMon. 2/m : P21/m
7.CC.10TamarugiteNaAl(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.15MendoziteNaAl(SO4)2 · 11H2OMon. 2/m : B2/b
7.CC.15KaliniteKAl(SO4)2 · 11H2OMon. 2/m : B2/b
7.CC.20Alum-(Na)NaAl(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20Lonecreekite(NH4)Fe3+(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20Alum-(K)KAl(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20Tschermigite(NH4)Al(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20LanmuchangiteTl+Al(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.25ZincovoltaiteK2Zn5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.25VoltaiteK2Fe2+5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.25MagnesiovoltaiteK2Mg5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.25PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe3+2Al(SO4)12 · 18H2OTet. 4/mmm(4/m2/m2/m) : I41/acd
7.CC.30KröhnkiteNa2Cu(SO4)2 · 2H2OMon. 2/m : P21/b
7.CC.35FerrinatriteNa3Fe(SO4)3 · 3H2OTrig. 3 : P3
7.CC.40GoldichiteKFe(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.45LöweiteNa12Mg7(SO4)13 · 15H2OTrig. 3 : R3
7.CC.50NickelblöditeNa2Ni(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.50BlöditeNa2Mg(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.50ChangoiteNa2Zn(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.55LeoniteK2Mg(SO4)2 · 4H2OMon. 2/m : B2/m
7.CC.55MereiteriteK2Fe(SO4)2 · 4H2OMon. 2/m : B2/m
7.CC.60NickelpicromeriteK2Ni(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Nickelboussingaultite(NH4)2Ni(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Katerinopoulosite(NH4)2Zn(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60PicromeriteK2Mg(SO4)2 · 6H2OMon. 2/m : P2/b
7.CC.60CyanochroiteK2Cu(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Mohrite(NH4)2Fe(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Boussingaultite(NH4)2Mg(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.65PolyhaliteK2Ca2Mg(SO4)4 · 2H2OTric. 1
7.CC.70LeightoniteK2Ca2Cu(SO4)4 · 2H2OMon. 2/m : B2/b
7.CC.75AmarilliteNaFe(SO4)2 · 6H2OMon. 2/m : B2/b
7.CC.80KonyaiteNa2Mg(SO4)2 · 5H2OMon. 2/m : P21/b
7.CC.85WattevilleiteNa2Ca(SO4)2 · 4H2O (?)Orth.
7.CC.85XocolatliteCa2Mn4+2(Te6+O6)2 · H2OMon. 2/m : P2/m
7.CC.90Eckhardite(Ca,Pb)Cu2+Te6+O5(H2O)Mon. 2/m

Fluorescence of AmmoniomagnesiovoltaiteHide

In UV light:
Not fluorescent.

Other InformationHide

Notes:
Soluble in water.
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for AmmoniomagnesiovoltaiteHide

References for AmmoniomagnesiovoltaiteHide

Localities for AmmoniomagnesiovoltaiteHide

Showing 5 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Bulgaria
 
  • Montana Province
    • Chiprovtsi Municipality
Dimitrova +2 other references
Germany
 
  • North Rhine-Westphalia
    • Cologne
      • Aachen
        • Alsdorf
Witzke et al. (2015)
Košek (2018)
Hungary (TL)
 
  • Baranya County
    • Pécs District
GEODA 2010/1 +1 other reference
USA
 
  • Ohio
    • Huron County
      • Huron River
Richards et al. (2017)
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